BackgroundPsychosocial stress profoundly impacts long-term cardiovascular health through adverse effects on sympathetic nervous system activity, endothelial dysfunction, and atherosclerotic development. Recreational Music Making (RMM) is a unique stress amelioration strategy encompassing group music-based activities that has great therapeutic potential for treating patients with stress-related cardiovascular disease.Material/MethodsParticipants (n=34) with a history of ischemic heart disease were subjected to an acute time-limited stressor, then randomized to RMM or quiet reading for one hour. Peripheral blood gene expression using GeneChip® Human Genome U133A 2.0 arrays was assessed at baseline, following stress, and after the relaxation session.ResultsFull gene set enrichment analysis identified 16 molecular pathways differentially regulated (P<0.005) during stress that function in immune response, cell mobility, and transcription. During relaxation, two pathways showed a significant change in expression in the control group, while 12 pathways governing immune function and gene expression were modulated among RMM participants. Only 13% (2/16) of pathways showed differential expression during stress and relaxation.ConclusionsHuman stress and relaxation responses may be controlled by different molecular pathways. Relaxation through active engagement in Recreational Music Making may be more effective than quiet reading at altering gene expression and thus more clinically useful for stress amelioration.

Total body or exchangeable potassium is used as an important indicator of body cell mass in the study of body composition. Body composition studies have been used extensively in the study of nutrition but recent work has questioned the validity of using changes in total body potassium as a measure of protein or nitrogen variation. To investigate the relationship between tissue nitrogen and potassium during nutritional manipulation 382 tissue samples from 100 surgical patients were analyzed by Kjeldahl analysis for nitrogen content and flame photometric analysis for potassium content. Nitrogen was related to potassium in parenchymous or cellular tissues by the relationship N (mg/g) = 14.7 + 0.17 K (microEq/g). The tissue content of the two elements was highly correlated (r = 0.80, p less than or equal to 0.001). For skeletal muscle a similar relationship existed N (mg/g) = 16.6 + 0.15 K (microEq/g) (r = 0.76, p less than or equal to 0.001). These relationships held for all nutritional states and degrees of trauma and nutritional manipulation. In sequential parenchymous tissue samples obtained from 15 subjects delta N/delta K = 0.17 +/- 0.03 mg/microEq. Nonparenchymous or acellular tissue nitrogen and potassium were poorly correlated. The potassium content was very low in these tissues. Exchangeable potassium was a valid indicator of parenchymous tissue nitrogen and as such a legitimate measure of nutritional status.